US4328747A - Character ring-selecting type printer - Google Patents

Character ring-selecting type printer Download PDF

Info

Publication number
US4328747A
US4328747A US06/131,561 US13156180A US4328747A US 4328747 A US4328747 A US 4328747A US 13156180 A US13156180 A US 13156180A US 4328747 A US4328747 A US 4328747A
Authority
US
United States
Prior art keywords
character
rings
ring
printing
type printer
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US06/131,561
Other languages
English (en)
Inventor
Hitoshi Fujiwara
Yousei Kawabata
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Suwa Seikosha KK
Epson Corp
Original Assignee
Suwa Seikosha KK
Epson Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Suwa Seikosha KK, Epson Corp filed Critical Suwa Seikosha KK
Application granted granted Critical
Publication of US4328747A publication Critical patent/US4328747A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
    • B41J—TYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS
    • B41J7/00—Type-selecting or type-actuating mechanisms
    • B41J7/48—Type carrier arrested in selected position by electromagnetic means
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
    • B41J—TYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS
    • B41J1/00—Typewriters or selective printing mechanisms characterised by the mounting, arrangement or disposition of the types or dies
    • B41J1/22—Typewriters or selective printing mechanisms characterised by the mounting, arrangement or disposition of the types or dies with types or dies mounted on carriers rotatable for selection
    • B41J1/32—Typewriters or selective printing mechanisms characterised by the mounting, arrangement or disposition of the types or dies with types or dies mounted on carriers rotatable for selection the plane of the type or die face being parallel to the axis of rotation, e.g. with type on the periphery of cylindrical carriers
    • B41J1/44—Carriers stationary for impression
    • B41J1/46—Types or dies fixed on wheel, drum, cylinder, or like carriers
    • B41J1/50—Types or dies fixed on wheel, drum, cylinder, or like carriers with one or more carriers travelling across copy material in letter-space direction

Definitions

  • This invention relates generally to a character ring-selecting type printer of the type used to print lines of characters in laterally spaced columns on printing paper and, more particularly, to a character ring-selecting type printer where the number of character rings is less than the number of laterally spaced columns which may be printed.
  • Conventional printers of the prior art tend to be large in size, noisy in operation, and difficult to miniaturize without the need for highly precision formed parts. The noise of operation and size of the printers reduces the number of locations where the printers may be conveniently used, and the requirements for precision in manufacture greatly increase the cost.
  • a character ring-selecting type printer especially suited for low noise operation and having a reduced number of precision formed parts.
  • the character ring-selecting type printer prints m laterally spaced columns and includes less than m character rings which are mounted with lateral spacing between ajacent character rings.
  • the character rings are translated in unison to enable one character ring to print in more than one column.
  • the number of character rings equals half of the number of printed columns when the cam provides translation equal to the spacing between printed columns.
  • the gap between adjacent character rings permits a construction which may be less precise than the construction required where adjacent character rings must be substantially in contact.
  • Another object of this invention is to provide an improved character ring-selecting type printer which has less character rings than the number of columns which can be printed.
  • a further object of this invention is to provide an improved type printer which is quiet in operation and can be miniaturized.
  • FIG. 1 is a perspective view of an impact type drum printer of the prior art wherein each hammer is used to print a plurality of columns;
  • FIG. 2 is a view showing the character locations on the character drums of the printer of FIG. 1;
  • FIGS. 3a and 3b are side elevational views, partially in section, of the printing mechanism of a character ring-selecting type printer of the prior art
  • FIG. 4 is a perspective view of the printer of FIGS. 3a and 3b;
  • FIG. 5a is a partial view of a character ring-selecting type printer in accordance with this invention.
  • FIG. 5b is a perspective view of a cam used in the printer of FIG. 5a;
  • FIG. 5c is a perspective view of a selective pawl used in the printer of FIG. 5a;
  • FIG. 6 is an alternative embodiment of a character ring-selecting type printer in accordance with this invention.
  • FIG. 7 is another alternative embodiment of a character ring-selecting type printer in accordance with this invention.
  • FIG. 1 shows a flying type drum printer of the prior art wherein characters for five columns are printed using the same hammer 4 and the same character drum 2.
  • characters 3 are provided, such as symbols, numerals, etc., for printing five columns, thereby providing for a total of twenty columns in the printer.
  • each character drum 2 is divided radially into five segments S 1 through S 5 , and within each segment the characters 3 for printing only one column are located.
  • a drum printer is generally not suitable for use in an office, in quiet places, etc., because the knocking sound made by the hammers 4 is loud and the printer is noisy.
  • the diameter of the character drums 2 is large. It is difficult to miniaturize the printer of FIG. 1, and the energy required to drive the motor 1 must be high as compared to a miniaturized printer.
  • FIGS. 3a, 3b and 4 Another conventional character ring-selecting type printer of the prior art is shown in FIGS. 3a, 3b and 4.
  • FIG. 3a shows a cross section and view of a printing mechanism
  • FIG. 3b shows a gear train for driving the printing process and the major elements in the restoring process.
  • FIG. 4 is a simplified perspective view of this printer.
  • Character ring 7 is mounted on a drive shaft 8 with each column being printed by an independent character ring 7, that is in contrast with the character drums 2 of FIG. 1, wherein a single drum accommodates a plurality of columns.
  • the outer peripheral surface of each ring 7 is divided into sixteen circumferential parts and twelve parts are devoted to characters 28 and four parts are blank.
  • each character ring 7 On the side surface of each character ring 7 is positioned a ratchet wheel 9 having teeth corresponding in spacing to the twelve characters 28 and a selective pawl 10 is positioned for engagement with each ratchet wheel 9.
  • a spring 11 is mounted inside each character ring 7, having one end thereof engaged in a v-groove in the drive shaft 8 so as to hold the character rings 7 and the drive shaft 8 together as a unitary structure.
  • each ring 7 rotates with the shaft 8 until selective actuation of each of the pawls 10 causes the pawls 10 to engage the associated ratchet wheel 9 and stop rotation of the associated character ring 7 with a selected character 28 in printing position.
  • the spring 11 is driven out of the v-groove leaving the character ring 7 at its selected position. It should be understood that each character ring 7 associates with an individual pawl member 10, ratchet wheel 9, inner spring 11, etc., and operates in a similar manner.
  • a selective gear 13 (FIG. 3b) is mounted on a frame 12 which also supports the drive shaft 8.
  • the selective gear 13 is only partially toothed and engages with an intermittent gear 14 to rotate the drive shaft 8 and the character ring 7 in a direction indicated by the arrow A in the drawing.
  • a spring 26 (FIG. 3b) used for restoring the character ring 7 and drive shaft 8, after printing is completed, to the standby position where they were located before initiation of the process of selecting characters.
  • a motor (not shown) rotates the intermittent gear 14 in the direction indicated by the arrow F through a gear train (not shown).
  • the drive shaft 8 rotates with the character rings 7 in the direction of arrow A.
  • the spring 26, for restoring the character ring 7 to a standby position is wound up. Then the character selecting process begins and is carried out as described above.
  • the selective pawl 10 is biased by the force of a selective spring 19 and is always primed for rotation in a direction indicated by the arrow C.
  • the pawl 10 instantly pivots when released by the bar 18 so as to engage in a tooth of the ratchet wheel 9 corresponding to the character that is to be printed.
  • the pawl 10 stops that particular associated character ring 7.
  • the trigger electro-magnet 16 is deenergized, the trigger bar 18 is pushed upward by the restoring force of a trigger bar spring 20 which was compressed by the prior motion of the attraction plate 17.
  • the selective pawl 10 remains engaged with the ratchet wheel 9, the trigger bar 18 cannot return to its initial position.
  • the character ring 7 is held by the selective pawl 10 and ratchet 9, when the drive shaft 8 rotates further, the spring 11 is forced up from the v-groove of the drive shaft 8, as previously described, and rides on the periphery of the shaft 8.
  • the drive shaft 8 comes to a stand-still when the last tooth of the selective gear 13 runs adjacent an untoothed sliding face c of the intermittent gear 14.
  • the character 28 on the selected character ring that is to be printed is present at the printing position 15. Otherwise, when no character 28 on a ring 7 is selected, a blank portion of the ring 7 is present at the printing position 15.
  • a crank 22 rotatably supporting the platen roller 21 for motion about a center of rotation 61 is then rotated in the direction of arrow D through a gear train from the motor (not shown).
  • the platen roller 21 is approaching the printing position 15.
  • the crank 22 is further rotated, the platen roller 21 rolls and presses a recording paper (not shown) against the selected character 28 through a ribbon (not shown) in the known manner.
  • a reset lever 24 and a reset lever shaft 25, joined as one piece, are rotated in the direction of arrow E by a cam 23 disposed on a side surface of the intermittent gear 14.
  • the selective pawl 10 rotates in the direction opposite of the arrow C to release from the ratchet 9 of the character ring 7.
  • the trigger bar 18 is able to return to its initial position in engagement with the selective pawl 10.
  • the intermittent gear 14 continues to rotate. At the moment that the printing is completed, contact of the last tooth b on the selective gear 13 with the untoothed sliding face c of the intermittent gear 14 is broken.
  • a printer with the above-described structure (FIGS. 3a, 3b and 4) has an advantage in that the noise emitted at the time of printing is of low level, because its characters are printed by a roller pressed against a character group which has been brought to rest.
  • the character rings 7 are close to each other.
  • the ratchet wheels 9 and the springs are disposed between each character ring 7.
  • Such a printer design has the disadvantage that the action becomes sluggish and erratic when the manufacturing accuracy of each part varies, as will always be expected to some degree.
  • the printer in accordance with this invention, is designed with consideration of the above-mentioned advantages and faults. It includes the best feature, i.e., quiet printing, that is found in a conventional printer of the type shown in FIGS. 3a, 3b and 4.
  • the printer of this invention is not only useable in the office, in quiet surroundings, and the like, but also by being miniaturized can be applied to a personal electronic calculator operated by an individual. Because critical parts are fewer in number and spaced further apart, the printer of this invention is more economical to produce and more reliable in operation.
  • FIG. 5a is a portion of a character ring-selecting type printer wherein only the circumferential portion, that is, an annular portion of the character ring 30 is laterally translated as explained more fully hereinafter.
  • the selective mechanism and the electro-magnetic devices are not translated but are fixed at a definite position.
  • FIG. 5b shows the shape of a cam 35 used in the printer of FIG. 5a
  • FIG. 5c shows the shape of a selective pawl 31 used in the printer of FIG. 5a.
  • the individual character print rings 30 have numeric characters or symbols along the surface periphery thereof.
  • a ratchet wheel 321 is located on one side of each character ring 30 and a ratchet wheel 322 is located on the other side of each character ring 30.
  • the character rings 30 are connected to a shaft 36 by means of an inner spring and v-groove in the shaft 36 as described above.
  • the shaft 36 is rotated by a motor (not shown) through a gear train comprised of a gear 37 driving a gear 60 which is fixedly attached to the shaft 36.
  • the character rings 30 are situated in the lateral positions indicated by the solid lines.
  • the ratchet wheel 321 is selected and brought to rest by the left (FIG. 5a) one 311 of the separated ends 311, 312 of the selective pawl 31 to select a character for printing.
  • a platen-roller 33 presses on the characters through a recording paper 34 and causes printing on the paper 34. Though inking means is not illustrated, the printing is done by means of a ribbon positioned between the characters and the paper 34 or by means of an ink roller.
  • the cam 35 has turned half of a revolution so as to move the drive shaft 36 laterally to the right (FIG. 5a) by a distance of one column spacing.
  • the character rings 30 are positioned so that even columns, that is, columns 2, 4, 6, etc., can be printed.
  • the character rings 30, and the drive shaft 36 to which the character rings 30 are connected translate to the position 30' indicated in the drawings with broken lines.
  • the motor gear 37 rotates the shaft 36' through the intermediate gear 60' and the process of selecting a character on each print ring 30' beings.
  • the spring 67 which is compressed when the shaft 36 translates laterally, constantly urges the end of the shaft 36 against the contours of the cam 35.
  • the cam 35 of FIGS. 5a and 5b is contoured for translation through a single columnar spacing.
  • the pawl 31 remains stationary as the shaft 36 with the character rings 30 translates, such that when printing the odd columns, the ratchet wheel 321 is engaged by the pawl arm 311 and when printing the even columns the pawl arm 312 is engaged with the ratchet 322.
  • each character ring 30' After a desired character is selected on each character ring 30', the characters are printed by the platen roller 33 and printing of one line is completed by the above-described two-step action. Then paper feeding, ribbon transport, etc., are performed in a known manner which needs no further description here as it does not constitute a novel portion of this invention.
  • the character rings 30 are constructed to move only between two columnar positions. But, by application of the principles of this invention, a character ring can be moved for three, four or more columns by changing the shape of the cam 35, or other translating mechanism which may be used. In this way, characters for a plurality of columns can be printed easily by one character ring having only a single band of characters on its periphery.
  • FIG. 6 is an alternative embodiment of this invention, showing a structure wherein the character rings 40 and the selective pawls 41 translate together. However, the electro-magnets 42 are fixed in position. Ratchet wheels 43 are affixed to only one side of each character ring 40 and the pawl member 41 has only one extension to engage with the teeth of the ratchet wheel 43. Other details of construction are similar to those illustrated in FIGS. 3a, 3b and 4, and the character rings 40 are mounted on a drive shaft 44. The character rings 40 rotate with the drive shaft 44, as described above, until a selection of a character for printing has been made. The number of character rings 40 is defined as m/2 where m is the total number of columns to be printed.
  • the number of selective pawls 41 is m/2, that is, there is one pawl for each character ring.
  • Each selective pawl 41 is positioned so as to be actuated by an individual electro-magnet 42 even in the condition where the ring and associated pawl are translated, as indicated by the reference numerals, 40' , 41' respectively, to print the adjacent columns. Translation is produced by a cam mechanism 35, or as shown in FIG. 7, and described hereinafter.
  • the character rings 40 and the associated pawls 41 translate laterally to the positions shown by the broken lines and given prime (') reference numerals. Then characters are printed at the translated position before the assembly returns to its initial condition.
  • m/2 character rings 40 print m columns of characters on a paper.
  • FIG. 7 is another alternative embodiment of a character ring-selecting type printer in accordance with this invention, wherein the primary mechanism necessary for printing, that is, a character ring 50, a selective pawl 41, an electro-magnet 52 and associated mechanisms, are unified for simultaneous lateral translation.
  • An electro-magnetic solenoid 54 has its plunger rigidly attached to a frame 55 to which a drive shaft 56 is mounted. In the manner described above, the character rings 50 are mounted to the drive shaft 56. When the solenoid 54 attracts the frame 55 to the left, (FIG. 6), the character rings 50 are in the position represented by the solid lines and odd columns are printed.
  • the character rings are translated such that spaced-apart character rings are used to print more than one column.
  • the character rings 30 translate but the pawl devices 31 remained laterally stationary.
  • character rings 40 and pawl mechanisms 41 translate in unison.
  • character rings 50, pawl mechanisms 51 and the driving electro-magnets 52 move in unison.
  • the character rings used in the three described embodiments, in accordance with this invention incorporate the components requiring accuracy in manufacture and assembly.
  • dimensional variations in the lateral direction may occur without influencing the mechanism for the adjacent column.
  • the printer in accordance with this invention eliminates parts which are complicated and require high accuracy in manufacture and assembly.
  • the space between character rings produces a printer which can tolerate reasonable lateral variation in each part. Because it also prints with a rolling, pressing motion, as described above, the printer is quiet in operation.
  • the embodiments described above incorporate character rings for printing every other column in what is intended to be a continuous line of printed columns.
  • the ratchet wheel 321 may be of extended lateral width such that the ratchet wheel 322 and the pawl arm 312 can be eliminated from the construction.
  • the pawl arm 311 remains positioned for engagement with the extended width ratchet 321 when the cam 35 produces translation.
  • the cam 35 may provide n levels of driving surfaces such that a character wheel 30 may print 2, 3 ... n columns and the number of character rings 30 which are required for a given width of printing paper may be further reduced.

Landscapes

  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Common Mechanisms (AREA)
  • Accessory Devices And Overall Control Thereof (AREA)
US06/131,561 1979-03-23 1980-03-19 Character ring-selecting type printer Expired - Lifetime US4328747A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP54-37562 1979-03-23
JP1979037562U JPS55138536U (ja) 1979-03-23 1979-03-23

Publications (1)

Publication Number Publication Date
US4328747A true US4328747A (en) 1982-05-11

Family

ID=12500952

Family Applications (1)

Application Number Title Priority Date Filing Date
US06/131,561 Expired - Lifetime US4328747A (en) 1979-03-23 1980-03-19 Character ring-selecting type printer

Country Status (3)

Country Link
US (1) US4328747A (ja)
JP (1) JPS55138536U (ja)
GB (1) GB2048782B (ja)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4533270A (en) * 1981-09-30 1985-08-06 Copal Company Limited Printing paper feed releasing device for printers
US5113759A (en) * 1989-05-15 1992-05-19 Citizen Watch Co., Ltd. Latch mechanism for small-size printer
US5158015A (en) * 1989-06-08 1992-10-27 Seiko Epson Corporation Compact print wheel printer with life extended character selection capability

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0442509A1 (en) * 1990-02-15 1991-08-21 Seiko Epson Corporation Miniature printer

Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3374873A (en) * 1964-02-17 1968-03-26 Codamite Corp Printing apparatus employing bidirectional stepping motors to position type member
US3385213A (en) * 1966-03-24 1968-05-28 Bull General Electric Type-drum mounting assembly in print drums
US3707122A (en) * 1970-07-13 1972-12-26 Peripheral Dynamics Print hammer mechanism with magnetic reinforcement to cath hammer
US3850097A (en) * 1962-03-08 1974-11-26 Mohawk Data Sciences Corp High speed printers with staggered fonts
US3990361A (en) * 1974-03-08 1976-11-09 Tokyo Juki Kogyo Kabushiki Kaisha Typewriting device
US4033256A (en) * 1974-05-09 1977-07-05 Kabushiki Kaisha Suwa Seikosha Printer
DE2830226A1 (de) * 1977-07-11 1979-02-01 Canon Kk Druckvorrichtung
US4161912A (en) * 1976-06-04 1979-07-24 Shinshu Seiki Kabushiki Kaisha Miniature printer
US4230039A (en) * 1977-05-20 1980-10-28 Citizen Watch Company Limited Drum printer with helically arranged type sets
US4244291A (en) * 1977-11-08 1981-01-13 Kabushiki Kaisha Suwa Seikosha Printer with a fixed and an axially movable character ring

Patent Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3850097A (en) * 1962-03-08 1974-11-26 Mohawk Data Sciences Corp High speed printers with staggered fonts
US3374873A (en) * 1964-02-17 1968-03-26 Codamite Corp Printing apparatus employing bidirectional stepping motors to position type member
US3385213A (en) * 1966-03-24 1968-05-28 Bull General Electric Type-drum mounting assembly in print drums
US3707122A (en) * 1970-07-13 1972-12-26 Peripheral Dynamics Print hammer mechanism with magnetic reinforcement to cath hammer
US3990361A (en) * 1974-03-08 1976-11-09 Tokyo Juki Kogyo Kabushiki Kaisha Typewriting device
US4033256A (en) * 1974-05-09 1977-07-05 Kabushiki Kaisha Suwa Seikosha Printer
US4161912A (en) * 1976-06-04 1979-07-24 Shinshu Seiki Kabushiki Kaisha Miniature printer
US4230039A (en) * 1977-05-20 1980-10-28 Citizen Watch Company Limited Drum printer with helically arranged type sets
DE2830226A1 (de) * 1977-07-11 1979-02-01 Canon Kk Druckvorrichtung
US4244291A (en) * 1977-11-08 1981-01-13 Kabushiki Kaisha Suwa Seikosha Printer with a fixed and an axially movable character ring

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4533270A (en) * 1981-09-30 1985-08-06 Copal Company Limited Printing paper feed releasing device for printers
US5113759A (en) * 1989-05-15 1992-05-19 Citizen Watch Co., Ltd. Latch mechanism for small-size printer
US5158015A (en) * 1989-06-08 1992-10-27 Seiko Epson Corporation Compact print wheel printer with life extended character selection capability

Also Published As

Publication number Publication date
GB2048782B (en) 1983-01-26
GB2048782A (en) 1980-12-17
JPS55138536U (ja) 1980-10-02

Similar Documents

Publication Publication Date Title
US3332343A (en) Selective hammer interposing means in high speed printers
US3884144A (en) Compact printer
US4328747A (en) Character ring-selecting type printer
US3378127A (en) Data printer with flexible print wheel
US3980169A (en) Impact control for single element printer
JPS58395B2 (ja) シリアルプリンタ
GB1568872A (en) Printing apparatus
US3875859A (en) High speed printer
US4449835A (en) Printing device
US4111117A (en) Selecting mechanism for printing type rings
US3253539A (en) Driving and supporting means for high speed printing drum
US4373439A (en) Character ring-selecting type printer
US3995547A (en) Compact flying printer
US4416557A (en) Serial printer
US3929067A (en) Impact printer
US3306191A (en) High speed printer
US4787762A (en) Power transmission apparatus
US4165687A (en) Printing equipment and method of operation thereof
US4452137A (en) Small-sized printer
US3291042A (en) High speed printing mechanism
US3795300A (en) Printing machine
GB2095181A (en) Character selection in type wheel printer
US4244288A (en) Flying printer
US4484520A (en) Compact printer with clutch
US3949664A (en) Compact flying printer

Legal Events

Date Code Title Description
STCF Information on status: patent grant

Free format text: PATENTED CASE